How to hunt a transmitter, run a contest exchange, read a grid locator, and link repeaters over the internet.
Syllabus: Operating activities: radio direction finding, contests, linking over the internet, exchanging grid locators
Compendium articles on the ideas in this lesson, beyond what the exam asks.
Practise the 11 pool questions for this group. Answers are shuffled, and every one comes with a one-line "why".
Radio direction finding (RDF) finds where a signal comes from: noise sources, jammers, or a hidden transmitter in a fox hunt. A directional antenna hears best when it points at the source.
RememberHidden transmitter hunt, interference, jamming: direction finding with a directional antenna.
A contest is an on-air competition to contact as many stations as possible in a set time. Be quick and clean.
| Good practice | Why |
|---|---|
| Send only your call and the required exchange | Saves time for everyone |
| Give your full call sign | Short or partial calls cause mistakes |
| Work each station once | Duplicates waste time |
RememberMinimum information: your call sign and the contest exchange.
A grid locator (Maidenhead grid square) names a geographic area with letters and numbers. Each extra pair of characters narrows it down.
You exchange grid squares in contests and on weak-signal modes. They mark where, not a direction or an elevation.
RememberLetter, letter, number, number (then letters): a place on the map.
VoIP is voice carried over the internet as digital data. A gateway is a station that connects other amateur stations to the internet.
| System | How you use it |
|---|---|
| IRLP | Links repeaters over the internet. From a radio, you control a node with DTMF tones |
| EchoLink | Needs no radio to start: use a computer or phone. Register your call sign and give proof of license first |
Memory hookIRLP: radio and DTMF keypad tones. EchoLink: log in, no radio needed.